Diabetic retinopathy

Date Updated: 08/13/2025

Overview

Diabetic retinopathy is a complication of diabetes that affects the eyes. It is caused by damage to the blood vessels in the light-sensitive tissue at the back of the eye, called the retina.

Diabetic retinopathy (die-uh-BET-ik ret-ih-NOP-uh-thee) can develop in anyone who has type 1 or type 2 diabetes. The risk increases the longer someone has diabetes and if blood sugars are not managed well.

At first, diabetic retinopathy might cause no symptoms or only mild vision problems. But it can lead to blindness, especially if diabetes or other health problems are poorly managed.

Symptoms

Some people have no symptoms in the early stages of diabetic retinopathy. As the condition gets worse, people may develop:

Spots or dark strings floating in their sight, called floaters.
Blurred vision.
Changes in vision.
Dark or empty areas in their vision.
Vision loss.

When to see an eye doctor

Proper treatment of diabetes is the best way to prevent vision loss. If you have diabetes, a yearly dilated eye exam with an eye care professional is recommended, even if your vision seems fine.

Developing diabetes when pregnant, called gestational diabetes, or having diabetes before becoming pregnant can increase your risk of diabetic retinopathy. If you're pregnant, your healthcare professional might recommend additional eye exams throughout your pregnancy.

Contact a medical professional right away if your vision changes suddenly or becomes blurry, spotty or hazy.

Causes

Over time, too much sugar in your blood causes damage to the tiny blood vessels that nourish the retina, cutting off its blood supply. In advanced stages of diabetic retinopathy, the eye tries to grow new blood vessels. These new blood vessels don't develop correctly and can leak or bleed easily.

There are two types of diabetic retinopathy:

Nonproliferative diabetic retinopathy. In this more common form of the condition, also called NPDR, new blood vessels aren't growing.

When you have NPDR, the walls of the blood vessels in the retina weaken. Tiny bulges stick out from the walls of the smaller vessels, sometimes leaking fluid and blood into the retina. Larger retinal vessels can begin to swell and become irregular in width. The condition can progress from mild to severe as more blood vessels become damaged.

Sometimes, retinal blood vessel damage leads to a buildup of fluid, called edema. This happens in the center portion of the retina, called the macula. If macular edema affects vision, treatment may be needed to reduce swelling and prevent lasting vision loss. Macular edema can happen in both nonproliferative and proliferative diabetic retinopathy.
Proliferative diabetic retinopathy. Diabetic retinopathy can get worse in this more severe type, also called PDR. Damaged blood vessels close off, causing the growth of new, irregular blood vessels in the retina. These new blood vessels can leak into the clear, jellylike matter that fills the center of your eye, called the vitreous.

In time, scar tissue from the growth of new blood vessels can cause the retina to detach from the back of your eye. If the new blood vessels block the flow of fluid out of the eye, pressure can build in the eyeball. This buildup can hurt the optic nerve, which carries information from your eye to your brain, resulting in glaucoma.

Risk factors

Anyone who has diabetes can develop diabetic retinopathy. However, the risk may increase as a result of:

Having diabetes for a long time.
Poorly managed blood sugar levels.
High blood pressure.
High cholesterol.
Pregnancy.
Tobacco use.
Being Black, Latino or Native American.

Complications

Diabetic retinopathy happens when blood vessels in the retina become damaged. Irregular blood vessel growth in proliferative diabetic retinopathy can lead to serious vision problems:

Vitreous hemorrhage. These new blood vessels are weak and can leak into the clear, jellylike matter that fills the center of your eye, called the vitreous. If the amount of bleeding is small, you might see only a few dark spots, called floaters. In more-severe cases, blood can fill the vitreous cavity and completely block your vision.

Vitreous hemorrhage by itself usually doesn't cause permanent vision loss, but the retina will need treatment focused on the underlying cause of the vitreous hemorrhage. The blood often clears from the eye within a few weeks or months. Unless your retina is damaged, your vision will likely return to its earlier clarity.
Retinal detachment. The irregular blood vessels that develop with diabetic retinopathy trigger the growth of scar tissue. This can cause the retina to pull away from the back of the eye. This can cause spots floating in your vision, flashes of light, missing areas of vision or severe vision loss.
Glaucoma. New blood vessels can grow in the colored front part of the eye, called the iris. These new blood vessels block the usual flow of fluid out of the eye. This can cause pressure to build up in the eye, leading to a condition called glaucoma. This pressure can damage the optic nerve, which carries images from your eye to your brain.
Blindness. Diabetic retinopathy, macular edema, glaucoma or a combination of these conditions can lead to complete vision loss, especially if health problems are poorly managed.

Prevention

You can't always prevent diabetic retinopathy. However, regular eye exams, good management of your blood sugar and blood pressure, and early treatment of vision problems can help stop vision loss.

If you have diabetes, reduce your risk of getting diabetic retinopathy by doing the following:

Manage your diabetes. Make healthy eating and physical activity part of your daily routine. Try to get at least 150 minutes of moderate aerobic activity, such as walking, each week. Take diabetes medicines or insulin as directed.
Monitor your blood sugar level. You might need to check and record your blood sugar level several times a day or more often if you're ill or under stress. Ask a healthcare professional how often you need to test your blood sugar.
Ask about a glycosylated hemoglobin test. The glycosylated hemoglobin test is also called the hemoglobin A1C test. It shows your average blood sugar level for the 2- to 3-month period before the test. Ask the health professional managing your diabetes what your A1C goal should be.
Manage your blood pressure and cholesterol levels. Eating healthy foods, exercising regularly and losing excess weight can help. Sometimes medicine is needed too.
If you smoke or use other types of tobacco, stop. Ask a healthcare professional to help you quit. Smoking increases the risk of many diabetic complications, including diabetic retinopathy.
Pay attention to vision changes. Contact a medical professional right away if your vision suddenly changes, becomes blurry, spotty or hazy.

Remember, diabetes doesn't always lead to vision loss. Managing your diabetes well can help stop problems.

Diagnosis

Diabetic retinopathy is often diagnosed with a dilated eye exam. For this exam, an eye care professional places drops in your eyes. The drops widen your pupils to give the eye care professional a better view inside your eyes. The drops can cause your near vision, also called reading vision, to blur for several hours.

During the exam, the eye care professional looks for irregularities in the inside and outside parts of your eyes.

Other tests that may be used include:

Optical coherence tomography: With this test, also called OCT, cross-sectional images of the retina show the anatomy and thickness of the retina. This helps determine how much fluid, if any, has leaked into retinal tissue. Later, OCT exams can be used to check if treatment is working.
Fluorescein angiography: After your eyes are dilated, a dye is injected into a vein in your arm. Then pictures are taken as the dye circulates through blood vessels in your eyes. The pictures can pinpoint blood vessels that are closed, broken or leaking.

Treatment

Treatment depends largely on the type of diabetic retinopathy you have and how severe it is. Treatment is aimed at slowing or stopping the condition from getting worse.

Early diabetic retinopathy: If you have mild or moderate nonproliferative diabetic retinopathy, you might not need treatment right away. Your eye care professional will closely watch your eyes to decide if and when you might need treatment.

Work with the healthcare professional who treats your diabetes to see if there are ways to improve your diabetes management. When diabetic retinopathy is mild or moderate, good blood sugar control can usually slow the worsening of symptoms.
Advanced diabetic retinopathy: If you have proliferative diabetic retinopathy, you'll need treatment. Macular edema is often treated as well, but your retina specialist helps guide the best time to treat. Depending on the specific problems with your retina, options might include:

Eye injections. These medicines, called vascular endothelial growth factor inhibitors, are injected into the fluid in the center of your eye, called the vitreous. The medicines help stop the growth of new blood vessels and decrease fluid buildup.

Three drugs are approved by the U.S. Food and Drug Administration, also called the FDA, for treatment of diabetic macular edema. These medicines are ranibizumab (Lucentis), aflibercept (Eylea) and faricimab (Vabysmo). A fourth drug, bevacizumab (Avastin), is often used off-label for the treatment of diabetic macular edema. Off-label means a medicine is used for a condition other than what the FDA approved it for.

These medicines are injected using topical anesthesia. The injections can cause mild discomfort, such as burning, tearing or pain, for 24 hours after the injection. Possible side effects include a buildup of pressure in the eye and infection.

These injections need to be repeated. In some cases, the medicine is used with laser photocoagulation.

Laser therapy. In this treatment, also called laser photocoagulation, laser beams of light are used to burn or shrink irregular blood vessels in the eye or treat areas of the retina without good blood flow. This can stop or slow the leakage of blood and fluid. Treating areas of the retina without good blood flow also reduces the growth of irregular blood vessels.

Laser treatment usually is done in a medical professional's office or eye clinic. You may need more than one session. Most people have blurry vision for about a day after the treatment. Some loss of outer vision or night vision after the treatment is possible.

Vitrectomy. Vitrectomy is a surgical procedure where small tools are inserted through the white part of the eye, called the sclera, into the vitreous cavity in the center of the eye. During the procedure, blood from vitreous hemorrhages can be removed. Retinal detachments and scar tissue related to proliferative diabetic retinopathy also can be treated. This surgery is done in a surgery center or hospital using local or general anesthesia.

While treatment can slow or stop the worsening of diabetic retinopathy, it's not a cure. Because diabetes is a lifelong health problem, future retinal damage and vision loss are still possible.

Even after treatment for diabetic retinopathy, you'll need regular eye exams. At some point, you might need added treatment.

Alternative medicine

Some alternative therapies might help people with diabetic retinopathy, but more research is needed to understand whether these treatments are effective and safe.

Let your healthcare team know if you take herbal or vitamin supplements. They can affect other medicines or cause problems in surgery, such as too much bleeding.

It's important not to delay standard treatments to try unproven therapies. Early treatment is the best way to stop vision loss.

Coping and support

The thought that you might lose your sight can be frightening, and you may benefit from talking to a therapist or finding a support group. Ask your eye care professional for referrals.

If you've already lost vision, ask about low vision products, such as magnifiers, and services that can make daily living easier.

Preparing for your appointment

The American Diabetes Association suggests that people with type 1 diabetes have an eye exam within five years of being diagnosed with type 1 diabetes. If you have type 2 diabetes, the group suggests getting your first eye exam at the time you're found to have type 2 diabetes.

If there's no evidence of retinopathy on your initial exam, the American Diabetes Association recommends that people with diabetes get dilated and have a complete eye exam at least every two years. If you have any level of retinopathy, you'll need eye exams at least annually. Ask your healthcare professional what is best for you.

The America Diabetes Association suggests that people with diabetes have an eye exam before becoming pregnant or during the first trimester of pregnancy. People who are pregnant need to be monitored closely and checked for 12 months after giving birth. Pregnancy can sometimes cause diabetic retinopathy to develop or get worse.

Here's some information to help you get ready for your eye appointment.

What you can do

Write a summary of your diabetic history. This includes when you were diagnosed, medicines you have taken for diabetes now and in the past, recent average blood sugar levels, and your last few hemoglobin A1C readings.
List all medications, vitamins and other supplements you take. This includes the dosages.
List your symptoms, if any. Include those that may seem unrelated to your eyes.
Ask a family member or friend to go with you. If someone comes with you, it may be easier to remember the information you receive. Also, because your eyes will be dilated, this person can drive you home.
List questions for your healthcare professional.

For diabetic retinopathy, questions to ask include:

How is diabetes affecting my vision?
Do I need other tests?
Is this health problem short term or long lasting?
What treatments are available, and which do you suggest?
What side effects might I expect from treatment?
I have other health problems. How can I best manage them together?
If I manage my blood sugar well, will my eye problems improve?
What do my blood sugar goals need to be to protect my eyes?
Can you suggest services for people with visual damage?

Don't be afraid to ask other questions you have.

What to expect from your healthcare professional

Your eye care professional is likely to ask you questions, including:

Do you have eye complaints, such as blurred vision or floaters?
How long have you had eye complaints?
In general, how well are you controlling your diabetes?
What was your last hemoglobin A1C?
Do you have other health problems, such as high blood pressure or high cholesterol?
Have you had eye surgery?